1. Field of the Invention
The present invention relates to the creation of real-time two or three dimensional Magnetic Resonance (MR) images of temperature changes for use during thermal therapy.
MR thermometry has recently gained attention because of the inportant role it plays during thermal therapy. In thermal therapy it is important to ensure that the required thermal dose is delivered to the entire target tissue, while at the same time the surrounding tissues are spared of thermal damage. MR thermometry can provide this useful information, as thermal maps can be constructed for the entire region of interest, and temperature variations of each pixel on the image can be monitored. This real time feedback can be used by the physician during the thermal therapy to ensure successful treatment of the target tissue.
2. Discussion of the Related Art
Many different temperature-monitoring techniques have been used to explore the possibility of using thermal mapping under MR guidance. Some of the techniques are based on measuring MR parameters like T1 relaxation time, diffusion coefficient of water and proton resonance frequency shift (PRF) which change with temperature. Different problems are associated with these techniques. Problems include temperature measurement accuracy, repeatability, calibration, and dependence on geometry and orientation.
These unsolved problems point to a need for better and more stable MR based thermometry.